How To Build Theory
by pananana
Summary: The weekend hadn't begun quite as Kate Beckett had imagined, but not even a murder on the beach was going to stop her from getting what she desired most - especially after building theory. Murder He Wrote ep insert. Of the naughty kind. Happy and maybe a tad bit naughty Christmas to you all!


**A/n:** Have a naughty Christmas! Also please endure the first little bit of episode reminder! The best bits come straight after!

**Disclaimer:** So not mine, though playing with them is damn fine.

Silence and the inky blackness of the sky combined with the bright twinkle of millions of stars had settled over the Hamptons. It seemed as though the day had given way to the calmness of the night. Inside of Castle's expansive and expensive villa, lights were dimmed creating long, sensual shadows which fell across luxurious furniture, soft rugs and statement art hanging on the walls.

Beckett had seated herself on the sofa, hoping that their weekend away could - at last - commence as planned. Her eyes tracked Castle's form, lingering on his hands that held a bottle of wine and two glasses. She could already taste the smoothness of Castle's expertly selected quality wine on her tongue. Admittedly, she was looking forward to another taste altogether - that of his lips pressing down on hers. Her rational mind, however, was refusing to give in to temptation and her needing to finalize things resurfaced with one last push of intelligent conversation.

"So Franklin was a meth kingpin, huh?" her smooth voice spilled over the quietness of the night while she gazed at Castle's nimble fingers pouring her a glass.

"Turns out all of his properties housed meth labs, which makes sense," Castle's deep, seductive rumble joined hers while he seated himself next to her and passed over a glass filled with deep, red liquid, "for someone who used to cook the books."

The glass, warmed by the temperature of his skin, slipped between her own digits and she felt electricity zing through her veins. It did not surprise her anymore that even indirect contact with him sent her blood singing.

Taking a sip of the wine, which indeed was almost annoyingly perfect in its bouquet, she continued, "That's why he was killed. It is a dangerous business." The richness of the drink hit her tongue and made her squirm in her seat. As if pulled by magnetic force her body edged closer to his broad, tempting form.

"Well, it's all about New York now."

The heavy wine bottle clinked on the table. Leaning towards Beckett, Castle gazed at her seductively.

"The boys can take it from there and we can pick up where we left off," the naughty twinkle in his his eyes made her heart beat a bit faster, "before this whole thing came to us."

Inching closer and closer to each other, their breaths mingled and pleasant tension mounted in anticipation. Beckett's cheeks reddened as his masculine scent - woody and enchanting - surrounded her. A sexy giggle escaped as her eyes dropped to his mouth. She could almost taste him, when…

Beckett's head shot up in confusion, "Yeah, but why did it come to us?"

Not missing a beat Castle's leering smile stayed in place. He would not be swayed, "Uh … the universe has a sense of humor, I suppose."

He resumed his attempt to meet his lips with hers, their plumpness and warmth drawing him in like a moth to a flame.

Alas the puzzled frown on Beckett's face remained in place and leaning back, her mind just refused to stop whirring. "No, no. I mean if this is about meth, then why wasn't he killed in New York?"

Castle's face soured up in the disappointment of a missed moment. A sarcastic, "Maybe the killer likes the beach," was grunted deep from his chest.

Her thoughts running a mile a minute, Beckett suddenly whipped around, her locks flying around her face. She sat her glass down on the tabletop and continued on as if Castle had not just been trying to reel her in for a make out session.

"No, I think there's gotta be more to it, Castle!" she shot up to her feet and started to pace around the sofa, while Castle, now deeply frustrated, bit his lip and rose to follow her.

"I mean, they knew about Lerner's boat..." her brow creased beautifully while she tried to figure out the sequence of events.

"You know what? I am sure the boys will figure it out."

Castle's attempts to appease her fell on deaf ears as her heels clicked on the floorboards. Her dress swayed around her hips as her shoulders and arms moved animatedly helping her theory run along, "...and that requires an intimate knowledge about Franklin's life. That's local knowledge."

Having followed her, Castle reached her back and placed his hands on the sculpted line of Beckett's shoulders. Squeezing lightly, he tried to ease the apparent tension, "Right, right, right. Maybe the killer just did his homework."

As if unwanted, she shrugged off his touch in a hurry, turned around to face him, an intense, concentrated look adorning her face. Her hands rose up in exasperation, "Yeah, but why would they go to all of that trouble? I mean, if he was a kingpin in New York City, why would they kill him out here?"

A line fell between her brows in frustration and her eyes penetrated his, waiting for that lightbulb moment.

"Ummm..." Castle's head tilted to the side in thought. His expression started off puzzled but then, as if all the fog had cleared, he smirked in satisfaction. "...unless part of the drug business was out here."

Realising where Castle was going with that, Beckett carried on in agreement, "That explains the helicopter. He needed the helicopter to transfer the drugs out here."

The distance between them was slowly, but steadily disappearing while their thought processes joined one another and the theory took shape.

Self-satisfied confidence grew around them as words spilled out faster and faster.

Castle took a step closer. "And why he slept with Natalia and greased palms…"

Beckett sucked in air, feeling his close proximity and shot of a rapid, "...he needed approval to get the helipad…"

His arm slid around her hip, the soft material of her dress slipping under his fingertips, creating delicious friction against her skin, "...yeah, much less risky to move your product in a helicopter..." He pulled her lower body towards his slowly while her hands settled on his muscular shoulders, "...rather than a boat or a car. No cop is gonna pull you over."

She could already feel the telltale signs of his arousal pressing against her, and with no precinct bustling in the background, but just his candlelit mansion livingroom, she was ready to give in. Rapid, excited breathing filled the air and her eyes once again slipped to his moving lips, eating up their mutual theory. "You know, Chief Brady said that their drug problem doubled over the past six months."

Castle's other hand settled itself on her lower back, bunching up a fistful of her dress. He roughly pulled her towards him, forcing a whoosh of air from her already overworked lungs. Her heaving breasts flattened against his broad chest. He traced the dark cavern of her mouth with his eyes, "Exactly when Franklin started using his helicopter."

An excited moan expelled from somewhere deep inside her. Mouths opening, they dove in to connect, anticipation unbearable, when Beckett suddenly pulled back regretfully. "I'm sorry Castle, but I think you should probably…"

Castle pinched his lips together trying to hold in a slew of very colourful curse words, nodded his head, "...call Ryan and Esposito."

"Yeah."

He let go and sidestepped Beckett, quickly walking away in search for his phone. Any slower and he would not be making any calls in the near future. Stalking down the hallway to the kitchen, he spotted his phone laying in the middle of the island. Grabbing it and roughly sliding his fingertips over the glossy screen, he sought out Ryan's number and pushed the phone towards his ear. Sighing in frustration, he raked his fingers through his hair, propped one hip against the island and waited for the inevitable "Hey Castle" on the other side of the line, silently damning Beckett's (well, his too, to be honest) devotion to her job.

Meanwhile, left standing in the middle of the living room, Beckett bit her lip and shook her head trying to clear both the arousal and rational thoughts flying around. Wanting to finally let go, she pinched the bridge of her nose, slid her fingers through her hair and shook out the locks. Smoothing her hands down her sides, she could still feel the slight tingle brought on by Castle's body pressed tightly against hers.

Refusing to be reasonable any longer and being drawn by his incredible pull, she turned on the spot and started to retrace his path to the kitchen. She could hear the muffled words about helipads, kingpins and drugs, as he explained their theory to Ryan. Setting a steady, yet silent pace, a mischievous glint shone in her eyes. She sneaked behind his dark, brooding form leaving a couple of inches between them, sucked in a courageous breath, the side of her mouth tilting upwards.

One would say it was his spidey sense that set him off, but in this instance it was his built-in "Beckett is here and she is up to no good" instinct that had him straightening his spine while goosebumps settled at the back of his neck.

Their connection was powerful enough for him to know that she was behind him. Her breath caressed his neck and warmth seeping through twin layers of clothing had him sucking in a lungful of air.

Ryan's questions started to fade in his ear and Castle stuttered slightly, when he felt Beckett's nails scrape down the wide expanse of his back, following the dips between his ribs around to his stomach, finding purchase just above his belt buckle. This move pressed her delectable form tight against his. He could feel the swell of her breasts, and the excitement at the very tips of them, pressing against his back, while her wicked grin found its place against his shoulder. Her nimble fingers caught against his belt buckle while her teeth sank into the firm skin covering his well-defined shoulder.

He heard the faint "You okay, Castle?" from Ryan, and squeezed out a somewhat steady "Yeah," asking if the detective got everything he needed. Following Ryan's affirmation, Castle dropped a hasty "Catch you later, man", slid his phone across the countertop while grabbing a firm hold of Beckett's wrist, that by now was applying steady pressure across the rapidly growing bulge below his belt. He pulled on her arm, twisted on the spot, and used his considerable body weight and height to pin her against the kitchen island.

Though startled by his move, Beckett eyes rose. She bit her lip in anticipation, and bending backwards slightly, met his heated gaze full on, daring him to continue.

He leaned over her, bending her backwards against the island, the solid muscle of his upper thigh situating itself between her legs. Their lower bodies pressed flush together creating delicious friction where both of them wanted it most. His eyes roamed over her form, following the vee of her dress where the charms of her necklace sparkled, drawing his eyes to the valley between her breasts. Lingering there for a moment, his heated look continued up along the line of her delicate neck. Castle lowered his head, his nose skimmed along the shadows surrounding her collarbones, up along the tendons of her neck. Taking a deep breath, he inhaled her scent.

His teeth grazed along her creamy flesh. Nipping at the delicate skin behind her ear, he growled, "That was naughty, Beckett."

His large palm tightened its grasp on her wrist, sending waves of electricity pulsing through her. She gasped as he possessively wrenched her arm. His muscular arms enclosed around her, pressing her wrist against the hard, cold surface of the counter, digging the curves of her fisted hand into the small of her back, locking himself tightly against her.

"I've warned you not to tease…" His evident arousal pressed against her, his voice deep and husky, darkness pooling in his eyes. Unable to withstand it any longer, he dove in and fused his mouth to hers in a rough, possessive clash of lips. Her guttural moan sent vibrations down his spine.

Losing himself in the moment, he barely felt the creep of Beckett's free hand climbing up his arm, over his shoulder, up the back of his neck till her fingers raked through his hair and pulled sharply while her teeth dug into his lower lip. "You know you love it, Castle," she all but growled into his mouth. She rocked her hips into his with a downward swoop against his hard thigh, putting pressure right where her body was begging for it. Heavy heat settled low in her abdomen.

Keeping a firm hold of her wrist, Castle held her tightly against him. Her breasts heaved against his chest while her tongue made wicked sweeps inside of his mouth. Her intoxicating scent, floral and sweet, yet somehow, deliciously salty, a mix of sea air and the fragrance of her own skin was making everything feel hazy.

He needed to feel more of her.

Sliding a hand around her hip, he trailed his fingers down the length of her toned thigh. Instinctively, she bent her leg lifting it up and curving it around his hip. The heel of her platformed shoe dug deeply into the back of his leg.

Castle grasped the back of her knee, shifting it even higher, opening her up so that her heated centre made direct contact with his muscular thigh. A shuddering moan against his lips and a gentle shiver that ran through her were the tells that she was enjoying their activities immensely.

Castle found the edge of her dress and slid his fingers under the hem. His nails applied enough force that they left a trail of tingling lines on her sensitive skin. The tips travelled up her long limb and grasped a handful of her pert ass in his large warm palm. Digging in, he applied enough pressure to have her grind against his leg.

"Now who's not playing fair, Castle?" her deep satisfied groan bounced off the walls of the kitchen. She needed to touch him, have his warm skin ripple under her fingertips, and while one of her hands had free reign to roam along the back of his head and neck, she craved more access. But he still had her other wrist pinned and she would be lying if she said it completely didn't do it for her. Trying to free herself, she pulled on her trapped arm, but that only spurred Castle to hold tighter.

Giving her ass a firm squeeze and slipping his fingertips under the edge of her lacy underwear, Castle traced the inside of her thigh, "You want to be set free? Ask for it. What do you want, Beckett?"

Her hips canted forward involuntarily. "More. I want more, Castle. More of you. I want to touch you," she breathed heavily.

"Nuh-uh, I got you just where I want you, Beckett." Pulling his fingers out of her underwear, Castle traced the roundness of her butt, hoisting her up on the counter. Moving over her hip, following the ridges of her ribs, he travelled further up over one perfect breast, his large palm covering it entirely. He could feel her sucking in a shaky breath followed by a low moan at the back of her throat.

"You _know_ I like touching things… you have no idea how glad I am that I can touch you like this, Beckett. Have you spread in front of me like this…" He tunneled his digits in her hair and pulled her eager mouth towards his, kissing her brutally. Tongue tracing the seam of her lips, diving into her warm mouth.

Mutual moans and groans filled the space around them and while their tongues played with each other, Castle finally let go of her trapped arm. Now free to roam, Beckett raked her fingernails through the short hair at the nape of his neck, enjoying the subtle movement of his shoulder and back muscles while he worked to slide of one of the straps of her dress down her shoulder.

Letting go of her mouth, Castle's gaze fell to her exposed breast, pleased to see she skipped wearing a bra. Her nipple, already hardened, was calling his name. Lowering his head, he blew right over it and wrapped his lips around the tip, applying gentle suction. Not to neglect its twin, he dragged down the other strap and wrapped his palm round the heavy flesh and squeezed.

Her back arched towards his mouth while a soft gasp left her parted lips. She leaned back, propping herself up on her bent arms. Excitement filled her as she watched Castle admire her - splayed across the kitchen island, breasts exposed, skirt of her dress bunched around her middle, soaked lacy underwear pressing against the front of his pants, legs wrapped around his hips.

"Castle! Enough!" she exhaled heavily. "Enough teasing! Enough looking! You've stared at me plenty."

She reached forward and grasped his belt buckle, flicked it open with skilled ease, popped the button and lowered the zipper. Her hands slid around his hips and inside his boxers, gave his ass a good grab and yanked both his underwear and pants down.

His erection sprang free, and while she would have loved to play with it, she had more pressing issues to attend to. Keeping a firm grasp of his round globes, she tugged him forward and ground his hard length against her swollen core. Her eyes slipped shut while he rubbed himself against her lace-covered centre, creating delicious friction against her pulsating clit. Both shuddered at the sensation, amazed at how they could work each other up so spectacularly. Rotating her hips in slow circles against his hard cock, Beckett's patience was disappearing at a rapid pace.

"Castle… please. Now." Her eyes bore into his, pupils blown black with arousal.

"Yes, but first..." He grasped her hips and pulled her off the counter. Applying gentle pressure, he turned her around, crowding himself behind her and rubbing his erection against her cheeks through the softness of her dress. Her palms landed on the counter with a soft thud to steady the them both.

"Like this. I want you like this," he whispered in her ear. Bunching the fabric of the dress in his fists, he dragged it up and over her butt and hooking his fingers at the elastic of her panties, he exposed her fully.

Her underwear slipped down her long legs tangling around her strapped platform sandals. Castle placed a large palm in the middle of her back and pushed her forward until she was bent over the kitchen island. Her breasts pressing against the cool marble surface sent a shiver running along the expanse of her back. The patterned fabric of her dress was a scrunched up mess around her waist, leaving her shoulders and ass exposed to the low lights of the kitchen. His hand slid up her vertebrae and tangled itself in her hair, gently tugging.

Her back bowed and she pressed her ass against him silently asking him to take her right there and then. He brought his hand around her hip, steadying her, nudged the tip of himself against her wetness. Beckett's body surged against his instinctively as he slipped inside.

Rewarded with _that_ particular gasp leaving Beckett's mouth - the one that was always present at that first joining between them - Castle retreated and then slowly, patiently, yet with such deliberate confidence rocked back in. Her head dropped forward at the feeling of fullness, her walls tightened against his girth. She was so close already, the constant tension between the two ignited her with such ease. She shuddered at the slick feel of him moving inside her and his answering groan spurred her pleasure onwards.

"Castle… more," she panted. Knowing what she wanted, Castle descended his think fingers between her legs and using the tips of two digits, circled around her clit. The reaction was instantaneous. Heat pooled low in her abdomen, while a flush spread across her chest, and tingles raced up her spine. Vision blurring, she screwed her eyes shut and floated in the feelings he created within her. One of his hands remained fisted in her hair, the other worked her centre with practiced ease, while he kept a deep, filling thrusting motion in and out of her depths. The only sign of his own weakening resolve was the deep rumble in his chest each time his hips slapped against the round globes of her ass.

His fingers, slick with her desire, traced rounds on her nub, taking her higher and higher. The repetitive action of his digits combined with the solid feel of his cock filling her over and over finally sent her into oblivion. Each orgasmic flutter of her inner walls gripped him tightly, while she panted out a string of expletives mixed with partial syllables of his name. It urged his hips to roll into hers harder and faster, prolonging her pleasure and heightening his. With one last jittery snap and a choked groan of her name, he spilled inside her.

Time stilled. The only sounds around the kitchen were those of exhausted breaths and the silent tremble of spent bodies. Gulping a mouthful of much needed air, Castle wrapped an arm around Beckett's waist and using the last vestiges of his strength hauled her against his chest. Boneless and shaky, she landed against him, the back of her head settled against his broad shoulder. His nose nuzzled her damp, musky skin. Beckett turned her head and their lips met in a slow, languid kiss.

"Hamptons Heat, huh?" she breathed into his mouth.

**A/n:** Castletasmic for begging, Trinxy for keeping me on my toes and Shena1 for being most awesome at kicking ass.


End file.
